Device for producing spherical charges from metals and alloys

ABSTRACT

A device is disclosed for producing spherical charges from metals and alloys in which the working vessel containing the melt of the metal or alloy having a melting point of up to 900*C, is filled with inert medium disposed above the melt, and having a diaphragm with a hole through which a stream of the melt is injected into the receptacle filled with a heat-resistant liquid. The working vessel is secured to the receptacle in such a manner that in the latter an auxiliary receiving chamber is formed between the butt end of the working vessel and the surface of the heat-resistant liquid of the receptacle, which auxiliary receiving chamber is filled with an inert medium, in which the stream of the melt is split to form spherical charges and allows the stream of the melt to be heated up to 1,100*C. The device envisages mixing of the melt prior to injection, which provides for a uniform distribution of the components in the produced spherical charges.

United States Patent 1 Likhtman et al.

[ July 24, 1973 DEVICE FOR PRODUCING SPHERICAL CHARGES FROM METALS AND ALLOYS [76] Inventors: Alexandr Efimovich Likhtrnan,

Kirpichnaya ulitsa 49 kv. 22; Vavil lvanovich Pyatyshev, 7 Parkovaya ulitsa 3/3 kv. 3; Valentin Romanovich Zagorodnikov, l Kozhukhovsky proezd, 19, korpus 3, kv. 64, all of Moscow, USSR.

[22] Filed: 1 Feb. 23, 1972 [21] Appl. No.: 228,667

[52] US. Cl 425/6, 264/13, 425/10 [51] Int. Cl. B29c 23/00 [58] Field of Search 425/6, 7, 10; 264/10, l2, l3, 5

[56] References Cited UNITED STATES PATENTS 3,436,790 4/1969 Simnad et al. 425/10 3,708,560 l/l973 Mayer et al 264/13 30 A, s 27 yl'la I :9 x fi w g 2 2; 4/ a Primary Examiner-Robert L. Spicer, Jr. Attorney-Holman & Stern [57] ABSTRACT A-device is disclosed for producing spherical charges from metals and alloys in which the working vessel containing the melt of the metal or alloy having a melting point of up to 900C, is filled with inert medium disposed above the melt, and having a diaphragm with a hole through which a stream of the melt is injected into the receptacle filled with a heat-resistant liquid. The working vessel is secured to the receptacle in such a manner that in the latter an auxiliary receiving chamber is formed between the butt end of the working vessel and the surface of the heat-resistant liquid of the receptacle, which auxiliary receiving chamber is filled with an inert medium, in which the stream of the melt is split to form spherical charges and allows the stream of the melt to be heated up to l,l00C.

3 Claims, 1 Drawing Figure l:7///////// 1, g 14 I6 DEVICE FOR PRODUCING SPHERICAL CHARGES FROM METALS AND ALLOYS BACKGROUND OF THE INVENTION The present invention relates to devices for producing spherical charges from metals and alloys, used in electronics and in the non-ferrous metallurgy industry. These devices make it possible to temperatures for heating metals and alloys of up to 1,100C and to manufacture spherical charges from metals and alloys having a melting point of up to 900C.

Spherical charges from a metal or alloy, having small dimensions ranging from 30 to 1,000 micromicrons, are used in electronics as emitters, bases or collectors; ball outlets in semi-conducting instruments; reference balls used for carrying out an express-analysis to determine the quantitative composition of alloys; small soldering charges for soldering the plates of semiconducting instruments. In non-ferrous metallurgy, spherical charges are used for preparing special alloys.

It is known in the art to have devices for producing spherical charges from metals and alloys, comprising a receptacle. which is heated, and filled' with heatresistant liquid and accommodates a working vessel which contains the melt of a metal or alloy the working vessel being filled with an inert medium disposed above the melt, and a diaphragm having a hole which is used for injecting a stream of the melt into the receptacle, under the action of the excessive pressure of the inert medium disposed above the melt in the working vessel.

The conventional devices make it possible to produce spherical charges from metals or alloys wherein a heating temperature of up to 450C can be used.

In these devices the working vessel filled with metal or alloy is sunk into a heat-resistant silicone liquid and is heated together with the latter up to the required temperature. With an excessive pressure being supplied into the working vessel, the stream of the melt is injected through the hole of the diaphragm into the silicone liquid, and spherical charges are formed as the stream is split under the action of the forces of surface tension.

These devices are disadvantageous in that it is not possible to produce spherical charges from metals and alloys having a melting point of above 400C due to the absence of a heat-resistant liquid capable of resisting higher temperatures.

Besides, the conventional devices do not employ any system for mixing the melt, which limits the scope .of their application owing to the alloys segregation, with respect to specific weights during the time the metal or alloy is being melted down andkept in this state.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a device for producing spherical charges from metals and alloys which have melting points of up to 900C, the components being distributed uniformly in every charge. 7

This task is accomplished in a device for producing spherical charges from metals and alloys, comprising a receptacle which is heated, filled with a heat-resistant liquid and accommodates a working vessel containing the. melt of a metal or alloy, filled with an inert medium disposed above the melt and has a diaphragm with a hole to inject a stream of the melt into the receptacle due to an excessive pressure of the inert medium in the working vessel, according to the present invention, the working vessel is secured to the receptacle in .such. a manner that an auxiliary receiving chamber is formed in the receptacle between the butt end of the working vessel and the surface of the heat-resistant liquid of the receptacle, the auxiliary receiving chamber being filled with an inert medium in which the stream of the melt is split to form spherical charges.

It is expedient to divide the working vessel by a partition into cavities that are intercommunicated at the side of the diaphragm of the working vessel and are alternately filled with the melt of metal or alloy owing to the pressure difference, which ensures mixing of the melt and the manufacture of charges of a homogeneous composition. a

The partition may be fashioned as' a hollow cylindrical tube.

Due to a higher melting point of the melt and mixing of the latter, the device according to the present invention provides for improved uniformity of the distribution of the components in the charges, which allows the percentage of the yield of good instruments in which the spherical charges are used, to be raised substantially. I

Besides, due to the higher melting point, the scope of applicationof the present device for producing spherical charges becomes considerably wider.

BRIEF DESCRIPTION OF THE DRAWINGS I The following description of an exemplary embodiment of the present invention is given with reference to the accompanying drawing which shows a general diagram of the present device in longitudinal section for producing spherical charges from metals and alloys.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT The device for producing spherical charges from metals and alloys by way of injecting a stream of molten metal or alloy, according to the present invention, comprises a quartz receptacle 2 which is heated, filled with heat-resistant silicone liquid 1 and accommodating a working vessel 3 made from refractory steel, containing the melt 4 of metal or alloy, filled with an inertmedium which is disposed above the melt 4, and a tantalum diaphragm 5 with a hole 6 through which a stream 7of the melt 4 is injected into the receptacle 2-due to the excesv sive pressure of the inert medium in the working vessel 3.

The working vessel 3 is secured to the receptacle 2 in such a manner that in the latter an auxiliary receiving chamber 8 is formed between the butt end of the working vessel 3 and the surface of the heat-resistant silicone liquid 1 of the receptacle 2, the chamber 8 being filled with inert medium in which the stream 7 of the a hollow cylindrical tube 9 into cavities 10 and-ll that are intercommunicated at the side of the diaphragm 5 of the working vessel 3 and alternately filled with the melt 4 under the action of the pressure difference providing for mixing of the melt 4 and manufacture of charges of a homogeneous composition.

The receptacle 2 is heated by means of a heater 12 made in the form of a coil which embraces the receptacle 2 and is coated with a heat-insulating material 13.

The receptacle 2 is hermetically communicated with the aid ofa rubber packing 14 to a casing 15 made from refractory steel. The rubber packing 14 is gripped by a flange 16 by means of bolts 17 with a cross-shaped head 18 and nuts 19.

The working vessel 3 is hermetically sealed by means of a metallic packing 20. Provided inside the working vessel 3 is a spherical washer 21 mounting the tantalum diaphragm with the hole 6, which is held with the aid of a nut 22 via a resilient packing 23 and a tube 24 accommodating the hollow cylindrical tube 9 which is fastened to a cover 25.

The cover 25 is hermetically communicated with the casing through a metallic packing 26 with the aid of bolts 27. The cover has three pipe connections 28, 29 and 30. The pipe connections 28 and 29 are designed to alternately supply the inert medium into the cavities l0 and 11, respectively. The pipe connection 30 is used for supplying the inert medium into the second auxiliary receiving chamber 8 to thereby provide counter-pressure and prevent the melt 4 from leaking during its displacement.

Secured to the casing 15 is a safety valve consisting -of a bushing 31, a ball 32, a spring 33, a bushing 34 and a locknut 35. The bushing 31 is packed in the casing 15 with the aid of a metallic packing 36. Passages 37 and 38 along which the inert medium passes are hermetically sealed from the outside by plugs 39 and 40, respectively.

The casing 15 has an annular groove 41 filled with water 42. From the outer side the groove 41 is hermetically sealed by an annular plug 43. In order to cool the rubber packing 14, the water 42 is supplied through a pipe connection 44.

The principle of operation of the present device for producing spherical charges from metals and alloys is as follows.

Melt is charged into the working vessel 3. The water 42 is supplied into the casing 15 via the pipe connection 44 to cool the rubber packing 14, whereupon the heater 12 isswitched on.

Concurrently, pressurized argon is supplied to prevent oxidation of the melt being heated and to effect its mixing.

With the pressurized argon being supplied into the cavity 10, the molten metal moves into the cavity 11, whereby the light and heavy components intensively move toward each other; as the light component that was originally in the upper portion of the melt 4 is now in the lower portion thereof and moves upward and the heavy component moves downward, the melt 4 takes the shape of a hollow cylinder. With the argon supplied into the cavity 11, the melt 4 moves into the cavity 10 to take the shape ofa solid cylinder, the light and heavy components still being capable of moving toward each other. With the process of mixing repeated several times, the components are distributed uniformly within the whole volume of the melt 4.

The lower part of the receptacle 2 is filled with the heat-resistant silicone liquid 1 to accelerate crystallization of the spherical charges.

With the argon being supplied simultaneously into both cavities l0 and 11 intercommunicated at the side of the diaphragm 5 of the working vessel 3, the melt 4 is injected from the working vessel 3 into the auxiliary receiving chamber 8 filled with argon, in which the stream 7 of the melt 4 is split and spherical charges are formed under the action of the forces of the surface tension.

In the present device the stream 7 of the melt 4 is split in the atmosphere of argon to be found in the auxiliary receiving chamber 8, which makes it possible to dispense with heating of the heat-resistant silicone liquid 1 up to the temperature of heating of the melt 4 and, accordingly, to raise this temperature from 450C to 1,100C. The heating of the melt 4 to the higher temperatures, carried out along with the mixing taking place under the action of the pressure difference, results in a more uniform distribution of the components in the melt 4 and, consequently, in the charges produced.

On leaving the hole 6 of the diaphragm 5, the stream 7 of the melt 4 falls out into separate drops which under the action of the forces of surface tension take the spherical shape and, upon reaching the silicone liquid 1, solidify and move down to the bottom of the receptacle 2.

The silicone liquid 1 is drained off and the spherical charges are discharged through a pipe connection (not shown in the drawing) of the receptacle 2.

The present device for producing spherical charges from metals and alloys makes it possible to manufacture charges of a correct spherical shape and size ranging from 30 to 1,000 micromicrons at a high rate of production, the contents of the components being homogeneous in every charge from'metals and alloys having a melting point of up to 900C.

The device has small overall dimensions and is convenient in use.

We claim:

1. A device for producing spherical charges from metals and alloys, comprising a casing; a receptacle and means for fixing said receptacle in said casing, said receptacle being filled with a heat-resistant liquid; a working vessel having a butt end and containing the melt of the metal or alloy, disposed in said receptacle, said working vessel being filled with an inert medium under pressure and disposed over said melt; diaphragm means disposed in interworking relationship with said working vessel having a hole therethrough so that the melt is injected in a stream into said receiving vessel under the action of the pressure of the inert medium in said working vessel, said working vessel being disposed in said receptacle in such a manner that an auxiliary receiving chamber means is formed between said butt end of said working vessel and the surface of said heatresistant liquid in said receptacle; said auxiliary receiving chamber means being filled with an inert medium, in which said stream of said melt is split to form said spherical charges; and means for heating said receptacle.

2. A device as of claim 1, wherein said working vessel is divided by a partition means into cavities intercommunicating with each other in the proximity of said diaphragm means; said cavities alternately being filled neous composition.

3. A device as of claim 2, wherein said partition means is fashioned as a hollow cylindrical tube. 

1. A device for producing spherical charges from metals and alloys, comprising a casing; a receptacle and means for fixing said receptacle in said casing, said receptacle being filled with a heat-resistant liquid; a working vessel having a butt end and containing the melt of the metal or alloy, disposed in said receptacle, said working vessel being filled with an inert medium under pressure and disposed over said melt; diaphragm means disposed in interworking relationship with said working vessel having a hole therethrough so that the melt is injected in a stream into said receiving vessel under the action of the pressure of the inert medium in said working vessel, said working vessel being disposed in said receptacle in such a manner that an auxiliary receiving chamber means is formed between said butt end of said working vessel and the surface of said heat-resistant liquid in said receptacle; said auxiliary receiving chamber means being filled with an inert medium, in which said stream of said melt is split to form said spherical charges; and means for heating said receptacle.
 2. A device as of claim 1, wherein said working vessel is divided by a partition means into cavities intercommunicating with each other in the proximity of said diaphragm means; said cavities alternately being filled with the inert medium so that said melt of said metal or alloy in said working vessel is alternately supplied to each of said cavities to effect mixing of said melt thereby to ensure manufacture of charges of homogeneous composition.
 3. A device as of claim 2, wherein said partition means is fashioned as a hollow cylindrical tube. 